That's just completely false:
Spanish civil war
Invasion of Poland
Stalin's victory in WWII
The Talibans
Iran-Iraq war
Spanish conquest of the Inca Empire
The Crusades
Etc, etc, etc...
Etc, etc, etc...
Even if you try to read it as good bad being subjective I don't think there's any fixed lens though which a history book would interpret the winners being the good guys in every conflict.
The bad guys for sure won the Iraq war.
“We have been the good guys in every single war.”
Rather than “ the good guys have won every single war”.
At least in my history books in school growing, my country was framed as the good guys and listed wars we lost.
That's true, but since they frequently lose, that produces a lot of history showing that the good guys lost.
Perhaps that's because you have no idea of the historic context for some of them? I completely disagree that "most wars are not good or bad". If you lived at the time of the wars in one of these countries you'd know very well who are the "good" and "bad" guys(sometimes, both sides can be bad like Stalin's Russia vs Hitler's Germany).
If you accept certain values as universal (freedom from tyranny, right not to get killed/raped/enslaved) it becomes pretty clear pretty quick which side (or sometimes both) are fighting to preserve some of these rights and which side is against. Which side has its soldiers motivated by an idea of making their country a safe place and which motivates them by letting them rape, pillage and having death squads right behind in case anyone tries to desert.
Also, how both sides treat civilians (own and opposing). For a recent example look at Hamas vs Israel. Hamas clearly states every Jew is a valid target for them, also they use their own civilians as human shields storing and launching weaponry from places like schools, hospitals etc. While Israel, when they are bombing residential blocks full of weapons do so called "knocking on the roof" (shooting on the roof of the building to give civilians a chance to escape). Often said civilians are blocked from escaping by Hamas.
If you have any doubts which side is bad, or good, or if both are bad find out what are they fighting for. Why did the war start? What values stand behind both sides.
Yes it is easy to tell. The good guys are those on your side, and the bad guys are the guys on the other side.
When your side kills civilians, it is really indirectly the fault of the bad guys for fighting and not surrendering. When the bad guys kills civilians it is because they have no regard for human life. When your side rapes it is just a few bad apples blown up by enemy propaganda. When the bad guys rapes it is because they are like evil animals. When your side perform ethnic cleansing it is an unfortunate but necessary step to preserve peace and safety for the good guys. When the bad guys perform ethnic cleansing it show they will murder everyone if they are not exterminated.
Sure somtimes you will have the good guys inexplicable turn evil, like the rugged freedom-loving Mujahedeen suddenly turning into the evil Taliban, but just remember to examine the ideals they fight for to determine wheter they are good or evil today.
If "your side" targets civilians on principle and has its written in its pamphlets it will continue to do so(or wants to "rid the earth of _insert-people-here_" your side is a bad one. As simple as that.
Look at any war in Europe in last 100 years. At least one if not both sides will openly say one or both of the above.
Distinguishing good vs evil is not that difficult. Most people learn the basics around 3 years old. But many regimes make it their priority to convince us words don't have concrete meanings and "everything is the same". No it isn't. Nazis using gas chambers on everyone that doesn't fit into their plan or Hamas slitting civilians and children's throats in Israel on purpose are not the same as combatants killing enemy soldiers.
I could even excuse Hamas shooting their dumb rockets at Israeli civilians, if they made an argument they don't have better guided ones, and to have any hope of hitting a military target they have to cover an area, but they don't make such claims. In fact we all know if they had better targeting capability they'd attempt to target softer civilian targets like schools, churches etc (exactly like what Russia does in Ukraine). Not military ones. We don't have to imagine. They tell us themselves in their constitution.
There is such a thing as a right and wrong and I explained how to distinguish one from another in the parent comment.
And what Israel does right now in Gaza is as bad as it gets. And Inam almost sure exactly what Hamas wants them to do. By the way, bombing civilian infrstructure and laying siege to civilians are both violations ofbthe Geneva convention. "Door knocking" or not, the result is some poor folks house is destroyed.
Actually, despite being inevitable to a certain degree, the Middle East and all of its conflicts is a prime example of a conflict without good and bad sides, isn't it? Which makes it so damn hard to solve.
Just a general remark, because press and media in Germany seem to have a hard time with that at the moment, not all Palestinians are anti-semites, critizing Israel is not tze same thing as critizing jews. And one can easily feel compassion with the innocent people suffering on both sides of this conflict without siding with Hamas. We should understand that, because otherwise we risk pissing off each and every Muslim for no good reason. And that wouldn't help, would it?
Remind me again who the USSR was fighting against in WWII?